Sharpener for cloth cutting machines



Nov. 5, 1940. J. B. G'URY, JR

SHARPENER FOR CLOTH CUTTING MACHINES Filed Aug. 31, 1959 v 2 Sheets-Sheet 1 J05 B. 61/219, J72, 22 9 NOV. 5, 1940. J. GURY, JR 2,220,762

SHARPENER'FOR CLOTH CUTTING MACHINES Filed Aug. 51', 1959 2 Sheets-Sheet 2 Awe/7% (955/? 73. 62/129,

2 'MZM/ Eg ne? Patented Nov. 5, 1940 UNITED STATES PATENT OFFICE SHARPENER FOR, CLOTH CUTTING MACHINES Claims.

This invention relates to sharpeners for blades in cloth cutting machines.

An object of this invention is to provide such a sharpener as an attachment, which will be 5 simple in construction and satisfactory in operation. In my co-=pending joint application, Serial No. 259,566, filed March 3, 1939, I have described and illustrated such a sharpener. One of the objects of this invention is to improve the mechanism of 'the type described in said application by simplifying the parts and mechanism and making other changes to increase efficiency. Specifically, an object of the invention is to provide improved means for securing contact between the I5 grinding wheels and the knife and for securing or permitting rotation of the wheels; to provide non-abrasive stops on cooperating grinding wheels; to provide improved means for rotatively adjusting a block carrying the grinding wheels;

to provide improved means for pivotally mounting on-the block the spindles carrying the grinding wheels; and to provide improved means for moving the wheels into andout of grinding position.

Other objects will be apparent from the following detail description, taken in connection with the accompanying drawings.

Fig. '1 is an end elevation showing a sharpener assembly with an end plate and a pressure foot of a cloth-cutting machine;

Fig. 2 is'a front elevation showing adetail;

Fig.3 is a side elevation;

Fig. 4 is a rear elevation, with sharpener wheels in extended or inoperative position;

Fig. 5 is a view similar to Fig. 4 with the sharpener wheels in operative or sharpening position;

Fig. 6 is a detail partly in section showing a grinding wheel and its method of support;

Fig. '7 is a detail partly in section showing mechanism forrotatively adjusting a block which carries the wheels;

Fig. 8 is an elevation showing the front face of a support;

Fig. 9 is an elevation showing the rear face of the support;

Fig. 10 is an elevation showing a'block and grinding wheel assembly; and

Fig. 11 is an exploded view showing separately the parts comprising the assembly illustrated in Fig. 10.

The attachment embodying this invention is made for a cloth cuttingmachine of commercial construction, which has a base to which is attached a pedestal supporting a motor and other 5Q mechanism, to reciprocate a vertical knife 4. in

such .a machine a cover plate 5 includes means for slidably supporting a pressure foot'bar.

The cover plate .5 includes a block or base 6 which has a vertical slot to accommodate a bar I carrying a pressure foot 8 at its lower end. The slot in the base 6 is covered by a plate 9. The'bar I has at one side a rack or serrations II]. which is engaged by a pawl H, having teeth at its inner end.- The bar is movable horizontally into and out-of engaging position by a'lever having a bifurcated end or fork (not shown) engaging about a depending pin l3 on the pawl II. It may be understood that upon release of the pawl II by moving it to the left, Fig. 1, through the medium of the lever engaging the depending pin I3, the pressure foot bar I with the pressure foot 8 may be raised or lowered. A knob i4 provides means for grasping the bar so that it may be raised or lowered when the pawl II has been released.

The sharpener assembly .is adapted to slide up anddown the lower portion of the bar I, carrying abrasive wheels 16 and Il. When .thesharpener is not in use theabrasive or grinding wheels may be swung away from the blade by means of mechanism which will be later described in detail, and the whole assembly may be secured in an extreme upper position adjacent the block 6 or the cover .plate 9. The sharpener assembly has a front plate l8 spaced forwardl from the bar 1 and adapted when theassem'bly is in uppermost position to lie against the front face of the plate 9 with its upper edge engaging the lower edge of a stop H] (see Fig. 2). The plate It! has an open vertical slot 20 at its upper end to accommodate a stud2l secured to the plate 9 and threaded to receive a nut 22, which when tightened engages the plate I8 and holds the sharpener assembly in its uppermost position adjacent the block 6.

A knob 23 is secured to and extends outwardly from the plate l8, by which the assembly may be moved along the bar 1.

So much of the mechanism as has been described in detail is substantially the same as 45 are hinged to the block 6|. The-support some (carrying the wheel I6) is moved by the lever 14,

the plate [8 are secured together by dowel pins 65 and screws 66. The support has a vertical slot 6'! to accommodate the bar 1.

The grinding wheels l6 and I! are so mounted by brackets 64 on the block 61 that they may be turned into and out of engaging position. They are also mounted in such a manner as to accomplish another object of the invention; that of mounting them in a slanting position so that by rotating the block 6| the assembly may be accommodated to a knife 4 of varying width. They are also mounted so that discs 68 secured to the wheels may engage each other.

The hinged connection between the block 6! and the wheel assemblies may now be described. The wheels 16 and IT with the discs 68 are rigidly secured to the hubs 69, by nuts 10, as best shown in Fig. 6. Each of the hubs 69 is mounted on a spindle 62 or 63 which is secured to and supported by a bracket 64.

The brackets 64 have hinged connections with the block 6|. The block is of I-form with hinge pins 12 and I3 rigid with the brackets and passing through the horizontal arms of the block.

It may now be understood that the wheels will be swung aside, as shown in Fig. 4, during the cutting operation of the machine and will be moved to engaging or grinding position, as shown in Figs. 3 and 5, only when the sharpener is to be used. Convenient means for accomplishing this movement of the wheels into and out of grinding position is accomplished by novel mechanism.

A long arm or crank 14 is rigidly secured to the lower end of one of the hinge pins 13. The outer end of the arm is arranged and adapted to be grasped manually so that the pertinent wheel assembly may be readily turned by grasping and moving the lever 14. The upper ends of the hinge pin 12 have meshing gears 15 rigidly secured to them. Thus when one wheel assembly this movement will be transmitted to the other wheel assembly (carrying the Wheel l1) so that both wheel assemblies will be moved in unison into and out of grinding position.

To secure tension, a short crank I6 is secured to the lower end of the hinge pin 73 which is pertinent to the assembly of the wheel I! and a spring Tl connects the two cranks l4 and 16. The spring is so mounted with respect to the cranks 14 and 16 as to exert tension to hold the wheel assemblies either in operative position, as shown in Fig. 5, or in inoperative position, as shown in Fig. 4. The spring also exerts tension to yieldingly hold the wheels against the blade when sharpening. I

The discs 68 act as stops to limit the movement of the wheel assemblies with reference to each other and prevents the abrasive cylinders of the Wheels from contacting each other, in which case excessive Wear would result. Experience has shown that the discs wear less by contact with each other than the cylinders do from contact with the knife.

Rotation of the wheels is brought about by their contact with the reciprocating knife. The block 6| is rotated on its pivot 18 just sufficiently to cause the wheels to bear with a slight tension (under the influence of the spring 11) against the blade and to separate the discs 68 from each other. With this arrangement, ideal sharpening conditions are provided and the wheels turn freely without any uneven wearing of their periphery. Any high points on the cylinders tend to wear away immediately.

While the hinge pins 72 and 13 are parallel and lie in a vertical plane, the wheels l6 and I1 and their spindles 62 and 63 are slanting. The wheel 16 slants downwardly and the wheel I! slants up wardly. That is, the wheels are supported with their axis oppositely positioned at an acute angle to a horizontal plane. Then by turning the block 6| the assembly may be adapted for a knife with a narrower blade. Thus, with the block in a vertical position or almost vertical, position, as shown in Figs. 4 and 5, the wheels will be adapted to rind a knife of extreme width, but by rotating the block 6| in a clockwise direction, Figs. 4 and 5, the assembly will be adjusted for a knife of lesser width.

Novel means are provided for rotatively adjusting the block 6|. The block 6| is pivotally mounted on a horizontal stud 18 rigidly secured to the support 60. A screw 19 on the end of the shaft 18 holds the block 6! in assembly with the support 60. Means for turning the block 6| about the stud 18 on its support 60 are illustrated in detail in Fig. '7. A bracket 80, which includes a collar, is loosely mounted by a pin 8| on the support 60, to which it is secured by a screw 82. A nut 83 is mounted in the collar of the bracket and has secured to it a thimble 84 by which the nut may be turned. A screw 85 is threaded in the nut 83 and has a crosshead 86 with a pin 8'! engaging in a hole 88 in the front or inner face of the block 6|. Thus by turning the thimble 84 the screw 85 may be moved to adjustably rotate the block 6 I.

A guard 89 is attached to the outer end of the shaft 62, which guard is placed to engage a part of the machine assembly, not illustrated in the drawings, to prevent the grinding wheels from coming in contact with and abrading the frame of the machine.

From the foregoing description it will be seen that the invention accomplishes its objects. Improved and simplified means have been provided for mounting grinding wheels on an assembly for sharpening blades of cloth cutting machines. Simple means have been provided for securing tension between the wheels and between the Wheels and the knife, permitting the wheels to rotate freely while grinding. Simplified means have been provided for moving the wheels in unison into and out of grinding position. Simple means have also been provided for mounting the Wheels in a slant position, so that by rotating the block to which they are hinged the mechanism can be adjusted to grind wide or narrow blades.

Various changes may be made in the details of construction within the scope of the appended claims, parts of the invention may be used without the whole, and various additions or improvements may be made while retaining the advantages of this invention. This invention has been described in part as an improvement upon a'device illustrated, described and claimed in a copencung joint application for patent, but it will be understood that, except as the appended claims require, it is not essential that. this invention be used with the specific mechanism or devices therein described.

I claim:

1. In asharpener attachment for a reciprocating vertical blade in a cloth cutting machine, the improvement comprising a support, a pair of abrasive wheels, a block mounted for rotative adjustment on the support, a pair of brackets, parallel hinge pins secured to the brackets and piv otally'con'necting the brackets with the block,

inter-meshing gears secured to the pins, and spindles supporting the wheels on the brackets respectively, said spindles being so supported in their respective brackets as to be oppositely slanted from a horizontal plane.

2. In a sharpener attachment for a reciprocating vertical blade in a cloth cutting machine,

the improvement comprising a support, a pair of abrasive wheels adapted tosimultaneously contact the blade on their periphery, a block mounted for rotative adjustment on the support, a pair of brackets, parallel hinge pins connecting the brackets with the block, and spindles for the wheels supported by the brackets at oppositely disposed angles from the horizontal.

3. In a sharpener attachment for a blade in a cloth cutting machine, the improvement comprising a pair of abrasive wheels, at block, a pair of brackets supporting spindles for the wheels, hinge pins connecting the brackets to the block whereby the wheelsmay be swung into and out of grinding position, and non-abrasive circular discs secured to the wheels respectively and adapted to contact each other on their peripheries.

4. In a sharpener attachment for a blade in r a cloth cutting machine, the improvement comport, abrasive wheels carried by said block, a 15 bracket on the support having 'a collar, a manually engageable nut mounted in the collar, a screw threaded in the nut, and means for connecting the screw and the block, whereby rotation of the nut will adjust the block on the sup- 20 port.

JOHN B. GURY, JR. 

